2 goredo -- djb's redo implementation on pure Go
3 Copyright (C) 2020-2023 Sergey Matveev <stargrave@stargrave.org>
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, version 3 of the License.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 // Out-of-date determination
31 "golang.org/x/sys/unix"
35 EnvOODTgtsFd = "REDO_OOD_TGTS_FD"
36 EnvOODTgtsLockFd = "REDO_OOD_TGTS_LOCK_FD"
40 OODTgts map[string]struct{}
42 FdOODTgtsLock *os.File
44 OODCache = make(map[string]bool)
45 FileExistsCache = make(map[string]bool)
48 func FileExists(p string) bool {
49 if exists, known := FileExistsCache[p]; known {
54 FileExistsCache[p] = true
57 if errors.Is(err, fs.ErrNotExist) {
58 FileExistsCache[p] = false
63 type TgtError struct {
68 func (e TgtError) Unwrap() error { return e.Err }
70 func (e TgtError) Error() string {
71 return fmt.Sprintf("%s: %s", e.Tgt, e.Err)
74 func isSrc(tgt *Tgt) bool {
75 if !FileExists(tgt.a) {
78 if FileExists(tgt.a + ".do") {
81 if FileExists(tgt.dep) {
87 func isOODByBuildUUID(tgt *Tgt) bool {
88 build, err := depBuildRead(tgt.dep)
89 return err != nil || build != BuildUUID
92 func isOOD(tgt *Tgt, level int, seen map[string]*Tgt) (bool, error) {
93 indent := strings.Repeat(". ", level)
94 tracef(CDebug, "ood: %s%s checking", indent, tgt)
95 ood, cached := OODCache[tgt.rel]
97 tracef(CDebug, "ood: %s%s -> cached: %v", indent, tgt, ood)
100 dep := DepCache[tgt.rel]
103 dep, err = depRead(tgt)
105 if errors.Is(err, fs.ErrNotExist) {
108 tracef(CDebug, "ood: %s%s -> is source", indent, tgt)
111 tracef(CDebug, "ood: %s%s -> no dep: %s", indent, tgt, tgt.dep)
113 OODCache[tgt.rel] = ood
117 return true, TgtError{tgt, ErrLine(err)}
120 DepCache[tgt.rel] = dep
123 if dep.build == BuildUUID {
124 tracef(CDebug, "ood: %s%s -> already built", indent, tgt)
125 OODCache[tgt.rel] = false
128 if !FileExists(tgt.a) {
129 tracef(CDebug, "ood: %s%s -> non-existent", indent, tgt)
130 OODCache[tgt.rel] = true
134 for _, ifcreate := range dep.ifcreates {
135 if FileExists(ifcreate.a) {
136 tracef(CDebug, "ood: %s%s -> %s created", indent, tgt, ifcreate)
142 for _, ifchange := range dep.ifchanges {
143 tracef(CDebug, "ood: %s%s -> %s: checking", indent, tgt, ifchange.tgt)
144 ood, cached = OODCache[ifchange.tgt.rel]
146 tracef(CDebug, "ood: %s%s -> %s: cached: %v", indent, tgt, ifchange.tgt, ood)
153 inode, err := inodeFromFileByPath(ifchange.tgt.a)
155 if errors.Is(err, fs.ErrNotExist) {
156 tracef(CDebug, "ood: %s%s -> %s: not exists", indent, tgt, ifchange.tgt)
158 OODCache[ifchange.tgt.rel] = ood
161 return ood, TgtError{tgt, ErrLine(err)}
164 if inode[:8] != ifchange.Inode()[:8] {
165 tracef(CDebug, "ood: %s%s -> %s: size differs", indent, tgt, ifchange.tgt)
167 OODCache[ifchange.tgt.rel] = ood
170 if InodeTrust != InodeTrustNone && inode.Equals(ifchange.Inode()) {
171 tracef(CDebug, "ood: %s%s -> %s: same inode", indent, tgt, ifchange.tgt)
173 tracef(CDebug, "ood: %s%s -> %s: inode differs", indent, tgt, ifchange.tgt)
174 fd, err := os.Open(ifchange.tgt.a)
176 return ood, TgtError{tgt, ErrLine(err)}
178 hsh, err := fileHash(fd)
181 return ood, TgtError{tgt, ErrLine(err)}
183 if ifchange.Hash() != hsh {
184 tracef(CDebug, "ood: %s%s -> %s: hash differs", indent, tgt, ifchange.tgt)
186 OODCache[ifchange.tgt.rel] = ood
189 tracef(CDebug, "ood: %s%s -> %s: same hash", indent, tgt, ifchange.tgt)
192 if ifchange.tgt.rel == tgt.rel {
193 tracef(CDebug, "ood: %s%s -> %s: same target", indent, tgt, ifchange.tgt)
196 if isSrc(ifchange.tgt) {
197 tracef(CDebug, "ood: %s%s -> %s: is source", indent, tgt, ifchange.tgt)
198 OODCache[ifchange.tgt.rel] = false
202 if _, ok := seen[ifchange.tgt.rel]; ok {
203 tracef(CDebug, "ood: %s%s -> %s: was always built", indent, tgt, ifchange.tgt)
204 OODCache[ifchange.tgt.rel] = false
208 depOOD, err := isOODWithTrace(ifchange.tgt, level+1, seen)
210 return ood, TgtError{tgt, err}
213 tracef(CDebug, "ood: %s%s -> %s: ood", indent, tgt, ifchange.tgt)
217 tracef(CDebug, "ood: %s%s -> %s: !ood", indent, tgt, ifchange.tgt)
221 tracef(CDebug, "ood: %s%s: %v", indent, tgt, ood)
222 OODCache[tgt.rel] = ood
226 func isOODWithTrace(tgt *Tgt, level int, seen map[string]*Tgt) (bool, error) {
227 _, ood := OODTgts[tgt.a]
230 if !isOODByBuildUUID(tgt) {
231 tracef(CDebug, "ood: %s%s -> already built", strings.Repeat(". ", level), tgt)
234 tracef(CDebug, "ood: %s%s true, external decision", strings.Repeat(". ", level), tgt)
237 ood, err = isOOD(tgt, level, seen)
242 flock := unix.Flock_t{
244 Whence: io.SeekStart,
246 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLKW, &flock); err != nil {
249 if _, err = FdOODTgts.Seek(0, io.SeekEnd); err != nil {
252 if _, err := FdOODTgts.WriteString(tgt.a + "\x00"); err != nil {
255 flock.Type = unix.F_UNLCK
256 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLK, &flock); err != nil {
262 func oodTgtsClear() {
264 flock := unix.Flock_t{
266 Whence: io.SeekStart,
268 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLKW, &flock); err != nil {
271 if err = FdOODTgts.Truncate(0); err != nil {
274 flock.Type = unix.F_UNLCK
275 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLK, &flock); err != nil {